1. Field of the Invention
This invention concerns the use of thermally expansible foaming materials, particularly thermally expansible foaming structural reinforcing materials, which are coupled to a beam-shaped carrier by a separate fastening means to provide additional localized stiffness to frames, rails, cavities and other structural members. Such a member may be useful in architectural, automotive, aviation, marine, or any other applications where increased support or stiffness would reduce vibration, noise, and/or fatigue propagation, or would provide reinforcement to enhance structural strength or provide energy management during crash, crush or impact encounters.
2. Description of the Prior Art
It has long been recognized that foamable materials may be used to bond together separate components. Structural foams, urethanes, and thermally expansible foaming materials have been used to enhance acoustic performance and provide structural rigidity. Examples of the use of thermally expansible structural reinforcing materials used on carriers in the automotive field are illustrated in U.S. Pat. No. 5,194,199 to Thum, U.S. Pat. No. 5,344,208 to Bien et al., and U.S. Pat. Nos. 5,575,526 and 5,755,486 to Wycech. Another example of the use of thermally expansible materials on a carrier and used primarily as a baffle composition is shown in U.S. Pat. No. 5,506,025 to Otto et al. An example of the use of foamable material on a beam-shaped structure in a piling is shown in U.S. Pat. No. 4,019,301 to Fox et al.
While such showings disclose various uses of expandable materials in reinforcing, baffling and sealant applications, there has developed a need for a simplified reinforcing member which will provide stiffening and reinforcement to a surrounding structural member. The use of expansible reinforcing materials which are initially dry and non-tacky are preferred in the manufacturing context. Such materials have shipping and handling advantages, notably this type of reinforcing material does not readily adhere to shipping containers, to workers during manufacture and installation, or to other critical surfaces which may come into contact with the material. By being non-tacky, these materials will not readily retain dirt dust or other contaminants. Additionally, these materials will not readily adversely adhere to a carrier positioned within the structural member which helps to position the reinforcing member prior to expansion of the reinforcing material.